add ukca_ref and point to dev spack-packages

[Whyborn]

See if we can trivially pull the other UKMO components from Github, using the same method as UM and JULES.

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🚀 The latest prerelease access-am3/pr23-7 at dd9adec is here: #23 (comment) 🚀

[Whyborn]

!redeploy

[github-actions]

🚀 Attempted to deploy access-am3 Prerelease pr23-1 with commit 11eaf5f

🖥️ Gadi Deployment ❌

[github-actions]

🚀 Attempted to deploy access-am3 Prerelease pr23-2 with commit 8973580

🖥️ Gadi Deployment ❌

[Whyborn]

!redeploy

[github-actions]

🚀 Attempted to deploy access-am3 Prerelease pr23-3 with commit 2e87980

🖥️ Gadi Deployment ❌

[Whyborn]

!redeploy

[github-actions]

🚀 Attempted to deploy access-am3 Prerelease pr23-4 with commit 2e87980

🖥️ Gadi Deployment ❌

[Whyborn]

!redeploy

[github-actions]

🚀 Attempted to deploy access-am3 Prerelease pr23-5 with commit b0ac0b1

🖥️ Gadi Deployment ❌

[github-actions]

🚀 Attempted to deploy access-am3 Prerelease pr23-6 with commit a16ad77

🖥️ Gadi Deployment ❌

[github-actions]

🚀 Attempted to deploy access-am3 Prerelease pr23-7 with commit dd9adec

🖥️ Gadi Deployment ✔️

Usage Instructions

access-am3, defined in ./spack.yaml, will be deployed to Gadi as:

• 2026.02.000 as a Release (when merged).
• pr23-7 as a Prerelease (during this PR).

This Prerelease is accessible on Gadi using:

module use /g/data/vk83/prerelease/modules
module load access-am3/pr23-7

When using the above modules, the binaries shall be on your $PATH.

For advanced users, this Prerelease is also accessible on Gadi via /g/data/vk83/prerelease/apps/spack/0.22/spack in the access-am3-pr23-7 environment.
Due to inode-saving measures, one will have to manually untar the environment metadata before environment activation with tar -xf .spack-env .spack-env.tar. It will require one to have write privileges.

Configuration Information

This Prerelease is deployed using:

• access-nri/spack on branch 0.22
• access-nri/spack-packages version 743214a989221d1723085d38671aa68add60ccbb
• access-nri/spack-config version 2026.02.000

If the above was not what was expected, commit changes to config/versions.json in this PR.